Insulin and plastic are not always happy campers together. If insulin crystallizes in plastic tubing, it is usually at the end of the infusion set. This can block insulin delivery and cause high blood sugars. When delivery stops, the pump will sound an occlusion alarm.
Much like a hematoma, a lump can be felt under the skin, usually associated with discomfort, warmth, and high blood sugars. No warning except highs and site discomfort!
Can occur to anyone. More likely in anyone who has ever had a skin infection (infected cut or scrape) in the past.
Usually starts when the site preparation is poor, sterile technique is not used, or the infusion set is not changed as recommended.
Site Bleed #1
Bleeding occasionally occurs near the skin surface and is seen as a red area (the small red spot to the right) at the infusion site. More common with metal needles, but can occur with any infusion set. Requires visual inspection.
Excess sweating can cause even well constructed infusion sets to come loose and fall out.
No warning except highs or a dangling infusion set!
Liquid adhesives like Skin Tac-H (Mason Labs) can be brushed onto the skin to increase adhesion. Skin Prep by Smith and Nephew is another one to try.
Use an odorless, antibacterial antiperspirant on the infusion site. Then swab lightly with an antiseptic pad and place a bioocclusive dressing on the skin.
Insulin leaks from your reservoir or infusion set are usually so small they are quite hard to detect. Your pump will not warn you of leaks. Insulin has a distinctive smell, often describes as creosote, or railroad ties, or Band Aids. Regular blood sugar tests are the only reliable way to detect leaks. No warning except for high blood sugars!
Air bubbles in the reservoir are not a problem unless they are large and enter the infusion line to replace insulin. If air bubbles are seen in the infusion line, an inch of air in the line is equal to half a unit of insulin. In most cases, up to an inch of air in the line is not of concern. Requires visual inspection.
The small bubble to the left in the picture can be ignored.
This problem appears to be more common with Teflon infusion sets, and is often encountered in golfers, tennis players, and active individuals. Blood sugars rise unexpectedly due to leakage of insulin along the Teflon tubing back to the skin. No warning is given except for high blood sugars! Occasionally, leakage of insulin out to the skin surface will be seen after a large bolus.